While I was thinking out pennybot I was wondering how I could get more debug information out as the single blinking led I have currently isn’t much. I remembered that the pic16f628 had usart onboard so a read up on it. Only two pins were needed with a max232 chip to handle the voltage pumping to a RS232 connection. Sounded pretty easy.
However before this point I needed a usb to serial dongle and a serial terminal program for my Mac. I already had a usb/serial adapter based on the pl2302 chip, a cheap ebay purchase. I searched around and found the necessary drivers for Mac so the pl2302 would be detected. Google is your friend for that. For a terminal program some people suggested using the ‘script’ command but that didn’t work very well. I then tried CoolTerm which was great and I fully recommend it.
For the max232 chip (and associated capacitors) I knew that I would want to use it both on my breadboard and possibly on future pic projects. A standalone board was the best option. I had a 4 pin (5v, GND, RX, TX) male header to connect the board to a breadboard or circuit and a stereo 3.5mm socket to connect the serial cable to. The serial cable was a recycle job were I got an existing 9 pin cable, cut off one end and wired up RX, TX and GND to a 3.5mm male stereo plug. It’s smaller than a full 9pin shell and is quite robust. Now I will be reserving the USART pins on pic projects in future and having a 4 pin female header so I plug in my max232 board when needed.
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